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Photometric, kinematic, and variability study in the young open cluster NGC 1960
Joshi, Y. C.; Maurya, J.; Panchal, A. +3 more
We present a comprehensive photometric analysis of a young open cluster NGC 1960 (= M36) along with the long-term variability study of this cluster. Based on the kinematic data of Gaia DR2, the membership probabilities of 3871 stars are ascertained in the cluster field among which 262 stars are found to be cluster members. Considering the kinemati…
Ground-based transmission spectroscopy with FORS2: A featureless optical transmission spectrum and detection of H2O for the ultra-hot Jupiter WASP-103b
Madhusudhan, Nikku; Nikolov, Nikolay; Constantinou, Savvas +11 more
We report ground-based transmission spectroscopy of the highly irradiated and ultra-short period hot-Jupiter WASP-103b covering the wavelength range ≈400-600 nm using the FORS2 instrument on the Very Large Telescope. The light curves show significant time-correlated noise which is mainly invariant in wavelength and which we model using a Gaussian …
Discovery of a mid-infrared protostellar outburst of exceptional amplitude
Minniti, D.; Stecklum, B.; Saito, R. K. +12 more
We report the discovery of a mid-infrared outburst in a young stellar object (YSO) with an amplitude close to 8 mag at λ ≈ 4.6 µm. WISEA J142238.82-611553.7 is one of 23 highly variable Wide-field Infrared Survey Explorer (WISE) sources discovered in a search of infrared dark clouds (IRDCs). It lies within the small IRDC G313.671-0.309 (d ≈2…
Galactic extinction laws - I. A global NIR analysis with 2MASS photometry
García-Lario, P.; Maíz Apellániz, J.; Barbá, R. H. +2 more
We have started an ambitious program to determine if the full diversity of extinction laws is real or if some of it is due to calibration or methodological issues. Here we start by analysing the information on near-infrared (NIR) extinction in a Two Micron All-Sky Survey (2MASS) stellar sample with good quality photometry and very red colours. We …
Significant luminosity differences of two twin Type Ia supernovae
Filippenko, Alexei V.; Foley, Ryan J.; Riess, Adam G. +5 more
The Type Ia supernovae (SNe Ia) 2011by, hosted in NGC 3972, and 2011fe, hosted in M101, are optical 'twins,' having almost identical optical light-curve shapes, colours, and near-maximum-brightness spectra. However, SN 2011fe had significantly more ultraviolet (UV; 1600 < λ < 2500 Å) flux than SN 2011by before and at peak luminosity. Several…
Spirals, shadows, and precession in HD 100453 - I. The orbit of the binary
Ménard, François; Pinte, Christophe; Maire, Anne-Lise +7 more
In recent years, several protoplanetary discs have been observed to exhibit spirals, both in scattered light and (sub)millimetre continuum data. The HD 100453 binary star system hosts such a disc around its primary. Previous work has argued that the spirals were caused by the gravitational interaction of the secondary, which was assumed to be on a…
A comprehensive study of open clusters Czernik 14, Haffner 14, Haffner 17 and King 10 using multicolour photometry and Gaia DR2 astrometry
Bisht, D.; Rangwal, Geeta; Yadav, R. K. S. +2 more
This paper presents an investigation into the four open clusters Czernik 14, Haffner 14, Haffner 17 and King 10, located near the Perseus arm of the Milky Way, using the Gaia DR2, 2MASS, WISE, APASS and Pan-STARRS1 data sets. We find normal interstellar extinction in 12 photometric bands for these clusters. Using Gaia DR2 proper motion data, the n…
No significant correlation between radial velocity planet presence and debris disc properties
Kennedy, Grant M.; Su, Kate Y. L.; Yelverton, Ben
We investigate whether the tentative correlation between planets and debris discs which has been previously identified can be confirmed at high significance. We compile a sample of 201 stars with known planets and existing far-infrared observations. The sample is larger than those studied previously since we include targets from an unpublished Her…
Kinematic modelling of clusters with Gaia: the death throes of the Hyades
Oh, Semyeong; Evans, Neil Wyn
The precision of the Gaia data offers a unique opportunity to study the internal velocity field of star clusters. We develop and validate a forward-modelling method for the internal motions of stars in a cluster. The model allows an anisotropic velocity dispersion matrix and linear velocity gradient describing rotation and shear, combines radial v…
A wide-area GMRT 610-MHz survey of ELAIS N1 field
Vaccari, M.; Taylor, A. R.; Ishwara-Chandra, C. H. +3 more
In this paper, we present a wide-area 610-MHz survey of the ELAIS N1 field with the GMRT, covering an area of 12.8 deg2 at a resolution of 6 arcsec and with an rms noise of ~40 $\mu$Jy beam-1. This is equivalent to ~20 $\mu$Jy beam-1 rms noise at 1.4 GHz for a spectral index of -0.75. The primary goal of the survey…